Protective paper strips for daylight loading film rolls



Sept. 27, 1932. E. OPFERMANN ET AL 1,379,443

PROTECTIVE PAPER STRIPS FOR DAYLIGHT LOADING FILI ROLLS Filed Oct. 8,1930 0/) afparr/imebfll'edpapel' (e/lwbs/c av/ aar/ I By Afforn yPatented Sept. 27, 1932 UNITED STATES PATENT OFFICE ERICH OPFERMANN, 0FIBERLIN-CHARLOTTENBURG, AND WALTER FISCHER, OF DESSAU IN ANHALT,GERMANY, ASSIGNORS TO AGFA ANSCO CORPORATION, OF BINGILAMTON, NEW YORK,A CORPORATION OF NEW YORK PROTECTIVE PAPER STRIPS FOR DAYLIGHT LOADING.FILM ROLLS Application filed October 8, 1930, Serial No. 487,372, and inGermany October 25, 1929.

Our present invention relates to photographic film rolls and moreparticularly to such film bands provided on both ends with a paper stripimpermeable to light rays.

The usual film rolls for daylight loading consist of a film band woundon a spool, the film being provided, for protecting it against the entryof light, with so-called allonges, i. e., strips of paper impermeable todaylight attached to both ends of the film. As it appears desirable tomake these protective paper strips nearly as stiff as the film, in orderto ensure a smooth forwarding of the hand through the apparatus,attempts have been made to stiffen the paper by coating it with layersof gelatin or cellulose derivatives. Moreover, it has been proposed forthe manufacture of the protective paper strip, to superpose two paperstrips and to unite them by means of an intermediate layer of awater-proof agglutinant.

According to our invention, protective paper strips having the stiffnessrequired, are made in a simple manner without application of specialstrengthening layers by preparing the strip from a parchmentized papercolored in the usual way so as to be lighttight.

The paper may be parchmentized in the usual manner, for instance, byshort immersion in strong sulfuric acid and quickly washj,

ing it. Unsized and sized paper may be used and, if desired, also paperconsisting of several layers couched one over the other. When usingsized paper, this is only parchmentized on its surface. It is alsopossible to unite a sheet of black and a sheet of red paper byparchmentizing them or to parchmentize two paper strips separately, towash them and then to couch them, while in a moist state, one on theother.

As compared with the protective paper strips hitherto used, those madeof parchmentized paper have not only the advantage of possessing agreater stiffness and tenacity but also ensure in consequence of thepores being closed by the parchmentizing process an enhanced protectionagainst light; furthermore they are more grease-proof and morewater-proof. They, therefore, protect the film against loss of moistureduring prolonged storage and delay its drying out which is apt to causebrittleness.

If desired, the parchmentized protective paper strips may be subjectedto mechanical glazing. Moreover, for reducing friction they may becoated in known manner with Wax, gelatin or the like. Generally, thepaper strips are colored in the known manner with dyes absorbing theactive light rays.

In the accompanying drawing Fig. 1 and Fig. 2 illustrate our invention.

Fig. 1 is a perspective view of a fragment of the film strip showing thejunction of the sensitized portion and the strip of parchmentized paper,the thickness being much exaggerated.

Fig. 2 is a plan of a fragment of the film strip showing the junction ofthe sensitized and protective bands.

What we claim is Film rolls for daylight loading comprising a film bandprovided at both ends with a protective stri of parchmentized paperimpermeable to light having about the same stiflness as the film band.

In testimony whereof, we affix our signatures.

ERICH OPFERMANN. WALTER FISCHER.

